Osg 2911408 Spiral Flute Tap 4-40 Unc Ticn Vanadium Hss

Product Description

The OSG 2911408 is a spiral flute tap designed for cutting 4-40 UNC right-hand internal threads in a wide range of ferrous materials. Manufactured from vanadium high-speed steel and finished with a TiCN (Titanium Carbonitride) coating, this tap delivers improved wear resistance and reduced friction compared to uncoated HSS tooling. The modified bottoming chamfer allows threading closer to the bottom of blind holes. With a 45-degree helix angle, the spiral flute design pulls chips up and out of the hole, making it well-suited for blind-hole applications where chip evacuation is critical. Overall length is 1.875 inches with a thread length of 0.196 inches.

This tap is intended for use in machining and fabrication environments where 4-40 UNC threads are required in materials including alloy steel, carbon steel, cast iron, stainless steel, die steel, and hardened steel. The H3 thread limit provides a controlled oversize fit suitable for standard tolerance threading in production and maintenance applications. It is a single-piece tap for use with standard tap handles or CNC tapping operations. Machinists, tool and die makers, and maintenance technicians working with small-diameter threads in ferrous materials will find this tap a direct fit for those applications.

Key Features

• 4-40 UNC thread form, 40 threads per inch, right-hand direction
• 45-degree right-hand spiral flute design promotes chip evacuation in blind holes
• Modified bottoming chamfer for threading close to the bottom of blind holes
• TiCN coating increases surface hardness and extends tool life in abrasive materials
• Vanadium high-speed steel substrate provides toughness across a broad material range
• H3 thread limit for standard controlled-oversize tolerance applications

Compatibility

Designed for cutting 4-40 UNC right-hand threads in alloy steel, carbon steel, cast iron, stainless steel, die steel, and hardened steel. Coolant-through is not supported on this tap.

Installation Notes

This tap should be installed in a properly sized tap wrench, tapping head, or CNC spindle with a rigid or floating tap holder matched to the shank diameter. Always ensure the workpiece is securely fixtured and the pilot hole diameter matches the recommended tap drill size for 4-40 UNC before beginning the tapping operation. Inspect threads for correct fit after tapping hardened or high-alloy materials, as tool wear accelerates in those applications. Follow applicable shop safety practices and machine guarding requirements when operating tapping equipment.